Assessment of Damage on Electric Transmission Wood Poles Caused by Pileated Woodpecker(Dryocopus pileatus)

摘要

Many electric utilities report heavy damage by woodpeckers on wood poles. In 2001, TransEn-ergie initiated a long-term field study on 2 twin-pole 120 kV transmission power lines; one locatedin the hardwood forest, and the other in the southern boreal forest. The goal of the study istwofold: 1) to understand the ecological aspects of the problem, and 2) to elaborate solutionsto reduce the damage. This paper focuses on the first two years (2001 and 2002) of the projectand presents data on damage intensity and distribution, pole utilization by woodpeckers and itdiscusses variables associated with damaged poles. On both lines, a total of 354 individual poleswere examined. The number of poles with woodpecker damage was 94 (42.9%) for the boreal site,while it was 39 (28.9%) for the line in the hardwood forest. The most severe damage was fromnesting or roosting cavities and most of them were excavated by Pileated woodpecker (Dryoco-pus pileatus). The average height of 133 nesting/roosting orifices made by Pileated woodpeckers(PW) on poles was 8.7 m. Including the new openings found in 2001 and 2002, the mean numberof openings/year since line construction was 5.7 in the boreal forest and 1.2 in the hardwood for-est, in the segments studied. PW selected poles with the largest diameter at breast height valuesfor excavating a nesting cavity. The large number of poles damaged over the years, suggests thatpole diameter is generally larger tan that of most trees in the surrounding forest. Results indicatethat PW tend to excavate a new orifice to reach an existing cavity when an old orifice is pluggedby maintenance crews.